PROJECT SUMMARY In response to RFA-HD-20-015 for the Population Dynamics Research Infrastructure Program FY 2020 (P2C), the University of Colorado Population Center (CUPC) requests renewal of infrastructure support for the five- year project period 2020?2025. With strategic investment of 15 years of center support from NICHD, CUPC has become a leading research institution in several areas of population science that include health disparities and behaviors, reproductive health, demography and genetics, migration and population distribution, and environmental demography. CUPC was an innovative leader in the emergence of demography and genetics, as well as environmental demography, as important areas of population science. It has gained substantial momentum over the past five years, and exciting new collaborative possibilities have emerged including ties with the University of Colorado?s (CU) Natural Hazards Center and new Earth Lab. NICHD support has also been leveraged to garner generous new investments from CU Boulder, and an agreement with CU Denver further solidifies CUPC as the hub of population science along the Front Range. Three specific aims guide the Center?s activities in the next five years: to (1) accelerate population science that matters; (2) fuel innovation in population science; and (3) continue and increase support for junior scientists. To reach these aims, we propose two cores. The Administrative Core maximizes affiliates? research time by reducing administrative burdens as well as by providing experienced, specialized assistance with grant preparation and submission. The Development Core undertakes a wide variety of activities to facilitate innovative scholarship, including offering a seed grant program, strong mentoring, working groups, speaker series, mini-conferences, and workshops. Important changes have been made in response to past successes, lessons learned, and new research opportunities. These changes include higher limits for seed funding, an annual grant writing workshop, and restructuring the center?s research leadership to further energize working groups and increase faculty leadership opportunities. Overall, the proposal outlines a research plan firmly grounded on a strong intellectual foundation that includes energetic new affiliates, several areas of high- impact emerging scholarship, and new commitments from home institutions. The next five years will build on CUPC?s critical momentum.